1. Field of the Invention
The present invention is directed to: screens for vibratory separators and shale shakers; methods for making such screens; and methods for reclaiming screen assembly parts for re-use and/or salvage.
2. Description of Related Art
A wide variety of industries use vibratory separators to separate materials such as liquids from solids or solids from solids. Typically such separators have a basket or other screen holding or mounting apparatus mounted in or over a receiving receptacle or tank and vibrating apparatus for vibrating the basket. One or more screens or xe2x80x9cscreen assembliesxe2x80x9d are mounted in the basket. Material to be treated is introduced to the screen(s) and separated material on top of the screen(s) flows off an end of an end screen.
With certain prior art screen assemblies used in vibratory separators and shale shakers, screening material is mounted on a frame or support and the screening material extends over substantially all of the frame""s or support""s area. In may prior art screens and screen assemblies, one, two, three or more layers of screen cloth, screen mesh, and/or other screening material are connected to a frame and/or to a support, e.g., by adhering with an adhesive, by bonding with epoxy material, by gluing with glue (e.g., but not limited to hot melt glue), or by bonding with plastic.
In many cases when a screen fails or exceeds its useful life, it is simply discarded. Typically none of the component parts is re-used in another screen or screen assembly.
There has long been a need, recognized by the present inventors, to recover and re-use parts of a vibratory separator screen or screen assembly which can be recovered; and to salvage those parts that are salvageable. There has long been a need, recognized by the present inventors, for making a screen or screen assembly for a vibratory separator that uses parts recovered from a screen or screen assembly, e.g. from a used screen assembly or from one that has been rejected during a manufacturing process.
The present invention discloses, in at least certain aspects, screen assemblies made with parts recovered from another screen assembly, e.g., a screen frame and/or a screen support. In one method according to the present invention, a first used or rejected screen is heated to powderize, degrade, turn to ash, break down and/or cook off (xe2x80x9cdegrade, etc.xe2x80x9d) adhesive, plastic, epoxy, bonding material, and or glue (e.g., but not limited to, hot melt glue) material which secures parts of a screen together and/or which secures layers of mesh or screening material on a screen together. Required heat can be provided in an oven or with heating apparatus (e.g. a blow torch), although these ovens and apparatuses are not equivalents. Such heating may also degrade, etc., paint and/or coatings on a screen assembly.
In certain embodiments, the present invention discloses, in at least certain aspects, methods for recovering parts of a screen assembly which result in: the degrading etc. of bonding material, adhesive, epoxy, plastic, or glue; in the loosening or freeing of screening material from a frame or support to which it had been secured so that the frame, support and/or the screening material can be salvaged; and/or in the degrading, etc., and/or removal of paint and/or coatings from parts of the screen assembly. If the screening material cannot be salvaged for re-use on another screen or screen assembly, it can be salvaged for re-use in other forms; for example, often stainless steel screening material is used on screen assemblies for shale shakers. A significant part of the screening material from a screen assembly can be recoveredxe2x80x94using methods according to the present inventionxe2x80x94and the stainless steel can then be used in applications other than on screen assemblies, e.g. in basic processes to make items out of stainless steel. If frames and/or supports recovered using methods according to the present invention cannot be recovered in sufficiently good shape for re-use in new screen assemblies or in other apparatuses or equipment, the metal in them can be salvaged for use in other applications or in basic manufacturing processes. In certain aspects this may be true when the frame or support of the screen or screen assembly is made from metals such as steel, carbon steel, stainless steel, aluminum, aluminum alloys, brass, bronze, zinc, and zinc alloys.
The present invention discloses, in at least certain aspects, a screen assembly for a vibratory separator or shale shake that has supporting apparatus with a plurality of openings therethrough, screening material on the supporting apparatus over the plurality of openings, the supporting apparatus recovered from a predecessor screen assembly by applying heat to the predecessor screen assembly, the predecessor screen assembly having the supporting apparatus and predecessor screening material secured to the supporting apparatus by securing material, the heat applied to the predecessor screen assembly sufficient to degrade, etc. the securing material so that separation of the supporting apparatus from the screening material and recovery of the supporting apparatus is facilitated.
The present invention discloses, in certain embodiments, a method for recovering parts of a screen assembly for a vibratory separator, the method including applying heat to a screen assembly, the screen assembly having supporting apparatus and screening material secured to the supporting apparatus by securing material, the supporting apparatus having a plurality of openings therethrough, and heating the securing material sufficiently to degrade, etc. the securing material to facilitate separation of the supporting apparatus from the securing material and recovery of the supporting apparatus. The present invention discloses, in certain aspects, a method for making a screen assembly for a vibratory separator, the method including recovering supporting apparatus from a predecessor screen assembly, the predecessor screen assembly with predecessor screening material on the supporting apparatus, the recovering done by a recovery method for recovering parts of the predecessor screen assembly, the recovery method including applying heat to the predecessor screen assembly, the screen assembly having the supporting apparatus and predecessor screening material secured to the supporting apparatus by securing material, the supporting apparatus having a plurality of openings therethrough, heating the securing material sufficiently to degrade, etc. the securing material to facilitate separation of the supporting apparatus from the securing material and recovery of the supporting apparatus, and connecting new screening material to the supporting apparatus.
It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:
New, useful, unique, efficient, non-obvious screen assemblies for vibratory separators and shale shakers parts or components of which are recovered from other screens or screen assemblies;
New, useful, unique, efficient, non-obvious methods for recovering such parts, including, but not limited to, frames and supports and screening material;
Such methods which facilitate the recovery for salvage of parts of such screen assemblies;
Such methods which include a step or steps of degrading, breaking down, turning to ash or powder, or cooking-off of adhesive, epoxy, glue, plastic, or bonding material;
Such methods and screen assemblies which provide a significant reduction in the cost of manufacture of screen assemblies for vibratory separators by re-using screen assembly parts; and
New, useful, unique, efficient, non-obvious methods for making screen assemblies from parts recovered by methods according to the present invention.
The present invention recognizes and addresses the previously-mentioned problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention""s realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent""s object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.